1. Field of the Invention
This invention relates to pneumatic tools, and more particularly, to dampening apparatus for substantially completely dampening pulsations in pressurized air lines from a pneumatically operated tool.
2. Description of the Prior Art
Pneumatic tools, such as drills and the like, which reciprocate due to air pressure being delivered to opposite sides of a piston, cause back pressure pulses in the pressurized air supply line. The pulses result from the switching of a valve which feeds the pressurized air to the opposite sides of the piston.
Since air is supplied at substantially constant pressure, the switching of the valve in the tool, which in turn routes the air to opposite sides of the piston within the tool, causes pulsations to be back fed into the air supply. The air pressure pulsations may cause malfunctioning of air supply valves of other tools controlling the air pressure from the supply line or manifold to which the pneumatic tools are connected. Where there are several tools operating from a single manifold, the air pulsations can have a severely adverse effect on the controlling valves of the tools and of the air manifold itself.
In some instances, a relatively simple accumulator may sometimes be used to help control the pulsations. However, such accumulators are generally not effective if there is more than one tool connected to the manifold. Moreover, the accumulators have only a relative limited effect on smoothing out the pressure pulsations.
The apparatus of the present invention overcomes the deficiencies of the prior art and provides a substantial dampening on pulsations caused by a pneumatic reciprocating tool.